"And after six days Jesus taketh Peter, James, and John his brother, and bringeth them up into an high mountain apart, And was transfigured before them: and His face did shine as the sun, and His raiment was white as the light" (Matthew 17:1-2).
This remarkable transfiguration of Christ was shown to the three disciples so that they could actually "see [Him] coming in His kingdom" (Matthew 16:28), as He will do someday when He returns to earth "in the clouds of heaven with power and great glory" (Matthew 24:30). This would ever afterward be an unforgettable experience which would strengthen the disciples for their critical future ministry.
James would become the first martyr, but his brother, John, would survive to bear the testimony far and wide for almost seventy more years. "And we beheld His glory, the glory as of the only begotten of the Father" (John 1:14). Peter also wrote of the amazing event: "For He received from God the Father honor and glory, when there came such a voice to Him from the excellent glory, This is my beloved Son, in whom I am well pleased. And this voice which came from heaven we heard, when we were with Him in the holy mount" (II Peter 1:17-18).
It is therefore very significant that the word "transfigured" (Greek, metamorphoo) is also applied to Christian believers in II Corinthians 3:18: "But we all, with open face beholding as in a glass the glory of the Lord, are changed [read `transfigured'] into the same image from glory to glory." That is, as we behold the glory of Christ in the mirror of the Scriptures, we ourselves are spiritually being metamorphosed into His own image. The marvelous transformation will be completed when He does come again and "change our vile body, that it may be fashioned like unto His glorious body" (Philippians 3:21). HMM